Lamp



H. A. DOUGLAS.

LAMP.

APPLICATION FILED FEB. 4. IgI.

Patented Nov. 9, 1920.

HARRY A.. DOUGLAS, 0F BRONSON, MICHIGAN.

LAMP.

Specification of letters Patent.

Patented Nov.. 9, 1920.

Application led February 4; 1918. Serial No. 215,332.

T 0 all 'whom it may concern.'

Be it known that I, HARRY A.. DOUGLAS, citizen of the United States,residing at Bronson, in the county of Branch and State of Michigan, haveinvented a certain new and useful Improvement in Lamps, of which thefollowing is a full, clear, concise, and exact description.

y invention relates to lamps of the class commonly' known as headlights,though the lamp of my invention is not to be limited to any particularuse to which it may be put. My invention relates particularly to thoselamps in this class that employ concave re-A flectors that are mountedto turn or tilt with respect to the casings that house the reflectors inorder that the direction of the light may be varied without adjustingthe position of the casings. in lamps that are upon automobiles, areusually mounted to swing upon horizontal axes in order that the lightmay fall upon parts of the roadway at differing distances from theautomobiles. l provide direct turning engagement of the reectors withtheir casings in order that the reflectors may be tilted.

The means for turning a reflector with respect to its casing is, inaccordance with another feature of my invention, an electromagneticmechanism Which is disposed within the casing and the space which isprovided between the casing and the reflector. This electro-magneticmechanism also enables me to eliminate the slot in the casing whether ornot the reflector has direct turning engagement with the casing.

will explain my invention more fully by reference to the accompanyingdrawing showing the preferred embodiment thereof and in which Figure 1is a view in longitudinal section of an electric headlight equipped inaccordance with my invention, a diagram of the circuit for controllingthe electro-magnetic operating mechanism being also shown in thisfigure; F ig. 2 is a detail view illustrating,preferred means employedfor assembling the reflector and its door and for assembling the glassor other light transmitting cover with the front end of the reflector;and Fig. 3 illustrates lthe pivotal union that is preferably employedbetween the casing and reflector to supplement the.

bearing that is afforded by the directly engaing reflector and casingportions.

ike parts are indicated by similar char Such reflectors, when employed Yacters of reference throughout the dierent figures.

The headlight illustrated is an electric headlight employing anincandescent lamp l which is coupled with the rear end of a concavereflector 2. This reflector is located mainly within the casing 3 thatis normally stationarily positioned upon the lamp bracket or othersupport. The casing 3 has its front portion 4 in the form of a zone of asphere. rthe reflector has a portion 5 which is also a zone of a spherethat is concentric with the Zone 4. The reflector portion 5 and thecasing portion i are in direct engagement forming a oint somewhat in thenature of a ball and socket joint whereby no gap need be introducedbetween the reflector and casing when the reflector is tilted to anextreme position and whereby no slot need be formed in the casing inorder that the reflector may be turned. "When the axis of rotation of'the reflector is to be substantially fixed with respect to the casing,diametrically alined pivot points 6 define an axis of rotation for thereflector which is inclusive of the common center of said Zone sections4 and 5. The portion 5 of the reflector is preferably formed byoutwardly turning the reflector and directing this outwardly turnedportion of the reflector toward the rear. This rearwardly extendingportion 5 of the reflector desirably engages the exterior of the casingand where the pivot pins 6 are employed the reflector portion 5 needonly be extended sufficiently to the rear to prevent the formation of' agap between the reflector and casing when thc reflector is turned to anextreme tilting position. The presence of the pivot pins 6, therefore,enables me to reduce the frictional engagement between the parts 4 and 5of the lamp, a feature which is advantageous when the reflector is to betilted by electro-magnetic mechanism, but which is not so important ifthe reflector is to be tilted by hand. The door 7 of the lamp carriesspring clips 8 and 9. rThe spring clips 8 constitute latches that may bepassed through slots l() (Fig. 2) in the reflector when the door andreflector are to be assembled. The clips 9 hold cover ll in front of thereflector. margin 71 of the door 7 presses the glass cover 1l againstthe ,felt ring 12 that engages the front rim of the reflector to guardagainst entry of dust'intoy the lamp structure.

the glass'` The front ery frequently these lamps are located in placesWhere it is not convenient to adj just the reflectors by hand when it isdesired to tilt them. For example, when these lamps are uponautomobiles, it is generally not feasible or convenient to engage thereflectors to turn them by hand and in order to avoid the employment ofoperating mechanism that would ma ke it necessary to slot the casings, Iprovide electro-magnetic reflector tilting mechanism within the casingthat may be controlled by switching mechanism accessible from thechauffeurs seats. In Figure l I have illustrated a solenoid 13 mountedin the'space between the rear ends of the reflector and casing. Thecorele of this solenoid has pin and slot connection- 15 with one arm ofa bell` crank 1G, this bell crank being pivotally mounted at its elbowupon the bracket 17 also within the casing. The other arm of the bellcrank has pin and slot connection 18 with a bracket 19 that is attachedto the rear end of the reflector upon theexterior thereof. Then thesolenoid is energized the reflector is tilted from its normal position.A spring 20 serves to return the reflector to its normal position whenthe .solenoid is denergized. In order that the presence of theelectromagnetic mechanism within the space between the reflector andcasing need not require the formation of a special opening for thepassage of the conductor 21 that leads to the solenoid, I pass thisconductor through the same electrical coupling 22 through which theconductor 23 passes to the lamp 1. The circuit connections illustratedare of the so-calle'd single pole arrangement, one terminal of the lampl and one terminal of the solenoid 13 being in grounded connection withthe casing 3, vthe casing in turn being connected with one terminal ofthe battery or other source of-current 2l. A switch 25 is shown betweenthe other terminal of the battery and the conductor 23 while a switch 26is shown between this saine terminal of the battery and the conductor2l. henever the reflector is to be tilted the switch 2U is closed toenergize the solenoid 13 and when the reflector is to be restored tonormal position the switch 26 is opened, the spring 2O then beingpermitted to restore the reflector to normal position.

The invention is not limited to all the precise details of' constructionshown in the drawings, and what I claim is:

1. A lamp including a casing open at its front end, the margin of thecasing at said end being contracted and curved inwardly, in the form ofa zone of a sphere, a reflector mounted within said casing, the frontend of the reflector being curved outwardly and backwardly in the zoneof a sphere fitting` closely against the outer surface of the front endof the casing, and diametrically opposite pivots between said backwardlycurved portion and the casing, the axes of said pivots intersecting thecommon center of said sphere Zones, whereby the surface of said spherezones are in close contact in all positions of the reflector.

2. A lamp including a casing the front end of which is curved inwardlyin the form of a Zone of a sphere having its smallest diameter at thefront edge of the casing, a reflector pivotally mounted in said casing,and having an outwardly and baekwardly curved flange bent to form thezone of a sphere having its greatest diameter at its rear edge, thesurfaces of said sphere zones fitting in sliding contact with each otherin all positions of the reflector. auddianietrically opposite pivotsbetween said flange and casing, said pivots being located in line withthe rear edge of said flange.

In witness whereof, I hereunto subscribe my name this thirtieth day ol'January A. D.,

HARRY A. DOUGLAS.

